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1.
An inherent tension exists between legal approaches to nature conservation and fisheries management in the European Union, as the former remains the remit of Member States while the latter is under the exclusive legislative jurisdiction of the European Community (EC). This tension is of particular importance when addressing the conservation of habitats or species that are under threat from fishing activities. This article examines recent developments in offshore marine conservation in the North-East Atlantic in light of the legislative developments and political frameworks that are currently evolving. By analysing the emergency closure of the Darwin Mounds area of cold-water corals and the UK pair-trawl ban, it becomes evident that the precautionary principle is a key factor in the tension between fisheries management and marine nature conservation, and is not always taken into account.  相似文献   
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The reduction of discards in European fisheries has been identified as a specific objective of the reform of the EU Common Fisheries Policy. To reduce the uncertainty in catch data and the socially unacceptable waste of resources that results from the disposal of catch at sea, a policy to ban discards has been proposed. Discard bans are currently implemented in Alaska, British Columbia, New Zealand, the Faroe Islands, Norway and Iceland. Experience from these countries highlights that a policy of mandatory landings can result in a reduction in discards, but relies upon a high level of surveillance or economic incentives to encourage fishers to land more of their catch. Discard bans will also not result in long term benefits to stocks unless total removals are reduced, through the avoidance of undersized, non-commercial or over quota catch. Experience shows that additional management measures are required to incentivise such a move towards more selective fishing. Success has resulted from the use of area closures and bycatch limits, with potential applications in EU fisheries. However, selective fishing will not be a panacea for the current state of European fisheries; discard bans and accompanying measures must be embedded in a wider management system that constrains fishing mortality to reasonable levels before sustainable exploitation can occur.  相似文献   
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随着城市化进程加速,城市范围迅猛扩大,人口急剧膨胀,高层建筑林立,地下空间开发规模化,面临着水资源贫化、地质环境恶化和地质灾害频发等巨大挑战.为了有效地应对挑战,迫切需要在城市多要素地质环境调查并建立完善的信息系统的基础上,开展面向“智慧城市”的精细、全息三维地质建模,即建立新型的城市“玻璃国土”,实现城市地质环境时空透视,然后利用传感器、物联网和云技术,建立城市地质资源、地质环境和地质灾害动态监测数据链,最后基于地质科学大数据的同化、融合和挖掘技术,进行智能预警和管控.  相似文献   
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随着长江禁渔国策的持续实施,长江干流和沿线通江湖泊中刀鲚资源及其关键栖息地将有可能得到恢复。为了确证长江禁渔后的2020年在鄱阳湖永修瓢头水域所采集到21尾刀鲚的洄游履历和资源类型,本研究采用电子探针微区分析技术(EPMA)对其耳石元素锶(Sr)和钙(Ca)的微化学特征进行了测定和分析。结果显示,所有个体耳石的Sr/Ca值变化较为复杂。自耳石核心至边缘Sr/Ca值分别出现了对应淡水生境的低值(<3)和对应河口半咸水或海水生境的中高值(>3),最后边缘部分再次出现了对应洄游返回淡水生境的低Sr/Ca值(<3)。Sr含量面分析图中也呈现出了对应淡水—河口半咸水—海水—淡水的蓝色—黄绿色、红色—蓝色变化的图谱;证明上述个体均具有明显的江海洄游特征,为典型溯河洄游型刀鲚。鄱阳湖永修瓢头水域是一处尚未曾正式报道过的洄游型刀鲚分布区。根据性成熟度和摄食情况可将瓢头水域刀鲚分为产卵场群体和非产卵群体两类。通过与鄱阳湖其他水域刀鲚情况的比较分析可以推定,两类刀鲚可能起源于鄱阳湖内两个不同区域的产卵场。对于产卵场群体而言,瓢头水域可能更主要起到产卵场的作用;而对于非产卵群体来说,瓢头水...  相似文献   
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The European fisheries management is currently undergoing a fundamental change in the handling of catches of commercial fisheries with the implementation of the 2013 Common Fisheries Policy. One of the main objectives of the policy is to end the practice of discarding in the EU by 2019. However, for such changes to be successful, it is vital to ensure stakeholders acceptance, and it is prudent to consider possible means to verify compliance with the new regulation. Remote Electronic Monitoring (REM) with Closed-Circuit Television (CCTV) has been tested in a variety of fisheries worldwide for different purposes and is currently considered as one possible tool to ensure compliance with a European ban on discards.This study focuses on Danish fishery inspectors and on fishers with REM experience, whose opinions are less well known. Their views on the landing obligation and on the use of REM were investigated using interviews and questionnaires, and contrasted to some fishers without REM experience. 80% of fishery inspectors and 58% of REM-experienced fishers expressed positive views on REM. 9 out of 10 interviewed fishers without REM experience were against REM. Participation in a REM trial has not led to antipathy towards REM. Fishery inspectors saw on-board observers, at-sea control and REM as the three best solutions to control the landing obligation but shared the general belief that the landing obligation cannot be enforced properly and will be difficult for fishers to comply with. The strengths and weaknesses of REM in this context are discussed.  相似文献   
7.
In this paper the discard ban policy within the Portuguese fisheries sector is discussed and the opportunities and impact in the fisheries economy that arise from sales of unwanted fish under the new landing obligation are evaluated. The decadal mean price of fish (€/kg, adjusted for inflation) rose from the 1940s until the 1970s, dropping thereafter. The yearly averaged economic income estimated for discards sales between 1969 and 2009 ranged from 419345€ to 2164379€. Discard ban sales could contribute from 10% to 53% of the total landed value and 9–34% of the total catches (landings + discards). Under a discard ban policy, the fishing sector with the largest economic contribution for total discards sales would be multispecies (54%), followed by trawl (26%) and seine (20%). On average, fishing sales contributed with 0.63% to gross domestic production (GDP) between 1938 and 2009. Discard sales can increase 1.07–1.46 times more than the fish landing contribution to GDP. After 1983 the average landings/imports economic ratio was 0.28:1, which means that fish imports surpassed landings economic value 3.57 fold. The discard ban policy can create economic opportunities in the national context thus helping to revitalize some specific fisheries sectors.  相似文献   
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The late Jurassic reconstruction for the Ul’ban synclinorium was proposed based on the lithological and structural similarity of the Upper Permian and Mesozoic complexes of the Yankan-Dzhagdy and Ul’ban lithotectonic zones of the Amur-Okhotsk fold system. It was suggested that the Un’ya-Bom subzone of the Yankan-Dzhagdy LTZ is a fragment of the Ul’ban synclinorium (including its eastern centroclinal closure) that was detached and westward displaced (for 400–600 km) in the first half of the Cretaceous.  相似文献   
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为掌握江苏全海域刀鲚资源状况,为后期长江禁捕效果评估提供支撑资料, 2017年5月、8月、11月与2018年2月在江苏海域(31°45′~35°00′N, 119°30′~125°00′E)分别进行了4次渔业资源调查, 并绘制了尾数资源密度与重量资源密度分布图, 利用SPSS 26软件对当年的刀鲚资源状况进行评估, 积累长江禁渔前刀鲚鱼种系统数据。结果表明: (1) 刀鲚除秋季(11月)与冬季(2月)存在部分群体分布于“机轮拖网渔业禁渔区线”(以下简称“禁渔区线”)外侧之外, 其余时间均在江苏近岸海域(江苏境内“禁渔区线”到海岸线之间的水域)栖息洄游, 江苏近岸海域是刀鲚主要栖息索饵水域; (2) 春季(5月)影响江苏海域刀鲚分布的环境因子较多, 主要有水温、盐度、溶氧、深度、透明度等, 这可能与刀鲚正处于产卵旺期, 对环境因子变化敏感有关; 夏季(8月)影响江苏海域刀鲚分布的环境因子是透明度, 此时刀鲚刚结束产卵不久, 返回近海后急需补充能量, 丰富的营养物质成为影响其分布的主要因素, 此时为北半球夏季, 江苏省境内60余条入海河流正值汛期, 入海河水携带大量的营养物质, 成为返海刀鲚优良的索饵场; 秋季水温降低, 刀鲚开始越冬洄游, 水温成为影响刀鲚分布的重要因素; 冬季, 随着刀鲚性腺再次发育成熟, 新一轮的生殖洄游开始, 刀鲚栖息水层上升, 水深成为影响冬季刀鲚分布的关键因素; (3) 与长江禁捕后其他研究者在长江口收集到的刀鲚规格、全长-体重拟合方程综合对比, 发现自“长江十年禁捕”逐步实施后, 刀鲚种群渔获规格逐渐增大, 全长、体重开始逐渐增长, 长江刀鲚种群呈现资源恢复趋势。  相似文献   
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近年来,生猪养殖业陆续开展了生猪禁养工作。通过划定生猪禁养区域,对禁养区内的"散、小、乱"养猪场进行清拆和整顿,再引进大型现代化生猪养殖场来发展企业化、规范化的生猪养殖是整治工作的常见思路,需要精准的数据、科学的理论作为支撑。本文以广州市增城区为例,从生猪禁养范围图制作和专题数据统计两方面探讨了测绘技术在生猪养殖业环保整治工作中的应用。通过数据提取、缓冲区分析、叠加分析、面的差异运算、地图编制等测绘技术的综合应用,证实了其服务于生猪养殖业环保整治工作的实用性、高效性和科学性,为各省市开展生猪养殖业环保整治工作提供了翔实的参考资料。  相似文献   
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